Does anyone know how I can use Terminal or another utility in Mac OSX to close or otherwise restart a given serial port? I have some software (HoudahGeo) and occasionally others that will crash or hang, leaving the serial port inaccessible to any other application. Sometimes unpairing the device will do it (BT335), sometimes it seems to time out and close (not sure since I don't know where the prefs or configuration for the ports are stored). I would assume there's a way to free up access to the port without restarting but I can't find it.

Also, is there a way to use the BT335 for realtime BT GPS AND make sure it's logging? The manual suggests it doesn't log once it's paired to a computer or other device via BT.

Just a couple of questions about this:Is the HoudahGeo a NMEA-compliant software?Do you have any other devices plugged in to the computer?Were you able to test the device with just one software running? All other programs closed down?

Another question, in what page of the unit's user manual does it state that the it would not log when it's paired to a computer or other device via bluetooth? Or, are you possibly referring to page 13 as stated below:

Note: When you connect BT-335 to your PC, BT-335 will enter the “data transfer mode”, it can not record the data in this mode. After you disconnect it from PC, please remember to power off and restart BT-335 to make it return to Data Logger mode.

HoudahGeo will do NMEA, among others. It works just fine with the BT335 but I have found it has a couple of bugs that are not relevant here. The question was whether anyone knew how to shut off and restart a serial port on Mac OSX. A sad fact of life with Mac software is that there isn't much that works with GPS and if you are testing software inevitably it will crash and it's a paint to restart the system just to free up the port. KeySpan, for example, once had a utility that helped with this.

The "not logging" inference I made was from (in my manual) page 11, but it's the same language. Can I assume you are saying I'm correct, it will NOT log data while connected via bluetooth?

Perhaps, you can search further online on how to restart a serial port on MAC OSX. If the software is causing the problem, possibly update to the latest version, reinstall the program, or reach out the manufacturer about this.

As for the 'not logging' interference, even though the device is paired up with the computer via bluetooth, it should still log data. The manual states that when you open up the Data Logger PC Utility software and starts to load data from the unit that is when it goes to 'Data Transfer' mode. In other words, the trackpoints are being loaded from the device and transferred to your computer. After you have obtained the data, you will need to restart the unit to be able to go back to the 'DataLogging' Mode.

Ah, that helps. I was afraid that if I used a device to check my position occasionally it would mess up the logs. It's kind of confusing but once I thought of downloading the log of the data as opposed to the real-time data I got it. Thanks.

Oddly enough there's nothing much out there about Mac serial ports. I can manually delete the whole port, but then I have to re-pair the device.

It might be possible to use a terminal application like ZTerm to manually manipulate this; what are the serial settings for the data coming in? 8-n-1? It's been a long time since I've used serial data applications and I can't remember this stuff.